In gas turbine engines, it is known to apply a compressive axial preload to rotors and other elements received around a same shaft. The preload may be applied for example through applying tension to tensioning rods, and the elongation of the tensioning rods is measured to determine if the load applied is sufficient. However, some defects may occur during application of the preload, for example one of the elements being locked in the shaft causing undesired gaps between the elements, deviations in squareness of the assembly, improper seating of the elements, etc., which may lead to the preload not effectively being applied despite the rods having undergone the required elongation.